Process of making binary asphaltic particles



Patented Oct. 11, 1949 PROCESS OF MAKING BINARY ASPHALTIC PARTICLESGilman B. Mollring, Los Angeles, Calif.

' NoDrawing. Application August 31, 1945,

Serial No. 613,961

4 Claims. (01. 117-21) This invention or discovery relates to a processfor transmuting asphalt, bitumen or similar material of a generalthermo-plastic nature into a multiplicity of tiny, cold, solid,non-agglomerating binary particles. Each particle of which contains aninner core of relatively low melting point asphalt and an outercapsule-like shell of relatively high melting point asphalt, or asphalttempering material as hereinafter described.

Applicant is aware that the prior art proposes asphalt in many forms ofdiscrete unitary particles, including powder, granules, filaments andother shapes of separated particles. Difficulty has been experienced inthe above mentioned methods in that the product as produced is expensiveof manufacture and restricted to the use of a single grade of highmelting point asphalt. My process as hereinafter described presents anew method for comminuting asphalt or bitumen and results in thecreation of a distinctly new product as will be apparent from thefollowing description of the product, process and claims.

It is an object of this process to produce a multiplicity of tiny, cold,solid, nonagglomerating particles of asphalt each particle of whichcomprises two distinct but inseparable parts fused together andcomprising an inner core of relatively low melting point asphalt and anexterior capsule-like shell of a relatively high melting point asphalt.The inner surface of said capsulelike shell adhering to the exteriorsurface of the asphaltic core by being fused thereon during the carryingout of the process. The exterior surface of said capsule-like shell ischaracterized by being substantially non-adherent and liquid solventsoluble at normal temperatures and pressures.

It is a further object of this process to provide asphalt or bitumen inan easily handled form,

preferably in bulk, inexpensive sacks or returnable containers and in aform which will prevent coalescense at the elevated temperatures andpressures experienced in storage or transit.

It is an additional object of this process to provide asphalt or bitumenin a form which will upon liquefaction amalgamate to become asubstantially homogeneous composite bituminous binder of a relativelymedium melting point suit able for coating aggregate material and thelike.

In practicing my process, hot liquid asphalt or bitumen of a relativelylow melting point is sprayed or atomized into a continuously moving bedor mass of substantially cool finely-divided asphaltic temperingmaterial having a relatively high melting point; as the hot needle-likestreams or sprayed particles of hot liquid asphalt impinge with thecooler powdered asphaltic tempering material, the action of impingementin conjunction with the sudden change of temperature causes the hotliquid asphalt to be transmuted from a hot liquid condition intocontracting, cooling discrete particles of solidifying asphalt, and itis during this brief interval of changing from a hot liquid into ,coldsolid particles that the thus formed asphaltic particles are coveredwith a uniform thickness of powdered high melting point asphaltictempering material which fuses in the same brief interval with theexterior surfaces of the said asphaltic particles to form protectivesubstantially capsule-like shells for the asphaltic particles as theycool and harden.

While I have described the inner core of the asphaltic particle as beingcomposed of a relatively low melting point asphalt, it is apparent thatboth the core and shell could be composed of the same grade of asphaltor the core could be composed of an asphalt having a higher meltingpoint. For the best results I prefer that the product be made in theorder stated.

While I have described the asphaltic shell as being composed of arelatively high melting point asphalt or bituminous tempering material,I mean to include any or all finely pulverized natural rock asphalts orcombinations thereof, or it may consist in whole or in part of apulverized high melting point refined asphalt.

In one modification of my process I have used 50% by weight of adiatomaceous earth to 50% of finely ground high melting point asphalt asmy tempering material, and it is apparent that more or less could beadded without departing from the spirit of the discovery. It is apparenttoo that both the core and the shell could be made of a filled asphaltas the term is understood in the industry.

What I claim is:

1. A process of manufacturing separated binary asphaltic particles,which comprises discharging continuous needle-like streams of relativelylow melting point hot liquid asphalt into a moving bed of coolfinely-divided tempering material comprising solid high melting pointasphalt while continuously moving the tempering material away from thepoint of impingement at such a speed that the liquid asphalt is dividedinto individual particles which are solidified and coated' with thetempering material.

2. A process of manufacturing separated binary asphaltic particlescomprising heating a relatively low melting point asphalt to an elevatedtemperature above the melting point thereof, spraying the molten asphaltin the form of atomized particles into a bed of cool finely-dividedsolid tempering material comprising high melting point asphalt, Whilesaid bed is continuously moving away from the point of impingement ofthe hot liquid stream of asphalt at such a speed as will convert theatomized particles into individual substantially spherical-shaped,separated solidparticles coated with thesaid asphaltic temperingmaterial and maintaining the temperatures of the particles and thetempering material such that the tempering material adheres to theexterior surface ofth mdividual particles by fusion thereon tomaintainthe particles of asphalt separated.

3. A process of manufacturing binary asphaltie particles comprisingheating a relatively high penetration asphalt to an elevated temperatureabove the melting point thereof, flowing the asphalt as thus heated inneedle-like streams into a bed of cooler high melting point pulverizedasphalt; which is; moving awayfrom the point-yof impingement, of thestreams of hot: liquid asphalt 317151191113 a speed. as will!comminutethe asphaltic liquidl into individual substantiallysphericalshaped: particles. of asphalt, and maintaining thetemperatures; of the hot liquid asphalt and the cool high melting pointpulverized solid asphalt such that the liquid asphalt particles aresolidified and the pulverized asphalt is heated sufliciently on contactwith the hot liquid asphaltic particles as thus formed to fuse with theexterior surface of the solidified particles to provide capsule-likeshells for same.

4. Av process according ta claim 1 in which the tempering material iscomposed ofapproximately 50% by weight of diatomaceous earth and 50% byweight of finely ground high melting point asphalt.

' GILMAN B. MOLLRING.

REFERENCES CITED The; following references are of record in the file: ofthis patent:

UNITED STATES PATENTS Number Name- Datev 2,396,910 Zai'sser" Mar. 19,1946 2,399,717 Arveson May- 7-, 1*946 FOREIGN PATENIS Number CountryDate 394,649 Great Britainr933

